I also purchased the transistors he sells for these kits, but my question is what power supply etc I need for this.
Reading all the info I can on here and on other websites has left me pretty confused as to the best way to complete this project. Some other builders are using massive caps. Is this the way to go? I need advice on the power pcb. Is there a suitable kit and what transformer would be needed?
Any help would be fantastic.
Thankyou.

Im also confused about the powersupply. I just purcased the torroid from the chematic (500va, 230-2x25v). It was very expensive.
The caps are expensive to. How much is needed?
Im also wonder if I must make it a regulated powersupply. will that affect thesound quality?
And how much fuses are recomended?

- big caps like > 40 K uF have small ESR but also a larger low impedance frequency width than smaller caps haven't. I think this is the reason of the big value, also for filtering and big inertia of course. If the soft and good sound of Hiragas' class A are famous, this is certainly one of the reason with the particular choice of the components. I surmise if Supercaps would existed before with such Farads an so low esr with such voltage capacity, Hiraga would probably had tested it. For the first Stage very low ESR should be avoided, but for the second stage of the Pi (reservoir caps) : a very low ESR is better !

- Check the ripple current capability of such caps to find the higher you can : BC, german brands...

- Check if you can source the genuine NOS transitors (metal can ? : there is a reason!)

- For filtering you can go maybe for a Pi if not exist in the kit. Inductance in opposite winding could be ok if can find it with such current (not to be worst than without...). Your major concern if Pi is choosed : first caps smaller or equal uF value in relation to the second caps stage of the Pi. "normal" ESR for the first stage but solid cap : Long Life, higher degrees your money can allow : 105c° 125 c° if you can ! Second Pi stage : high ripple current & very low ESR large uF value (40 k Uf minimum x the total needed in the genuine shematic).

- for input stage go with a very good quality input cap if exist or if no input trafo : e.g. a MIT RTX or a Riven Paper, Amphom in oil/wax....

But we haven't not to be closed minded : if fast regulated works : go for a fast linear one... then compare, keep the best, and please testimonie after for us !

Reading all the info I can on here and on other websites has left me pretty confused as to the best way to complete this project. Some other builders are using massive caps. Is this the way to go? I need advice on the power pcb. Is there a suitable kit and what transformer would be needed?
Any help would be fantastic.

I would not recommend more than 35-0-35V, absolute max. Make sure you use huge heatsinks, the biggest you can find. Class A generates lots of heat, even at low volume. Some PSU help can be found here.
Cheers,

I now have the boards and the components, but I miss the chematics. The original (on the homepage for the amlifier, 30w super class a) have other locations for the components. Does anyone have a schematics for the blue, double layer boards?

Jims Audio is not associated with the Jean Hiraga site.
They state that the schematic and parts list are emailed to you at
the time of purchase with shipping advice, if you bought from them.
For past orders they have done this. Have you checked your email?

I would not recommend more than 35-0-35V, absolute max. Make sure you use huge heatsinks, the biggest you can find. Class A generates lots of heat, even at low volume. Some PSU help can be found here.
Cheers,

Jacques

I also recommend no more than +/-30v, a long ago i did the Hiraga 30w and i want to improve the power and to do that job you first incrise supply voltage ofcourse, but every single of my couple efforts failed because when i tried to increase rail voltage more than 25v it starts to oscilates and unbalanced bias problems occured, to top it off i blow out quiet many couple of output transistors

If you wanna try , feel free but be cautious about bias and offset to not let the output transistors burn out( as i did , you must always connect an amp. meter to the positive rail to be able to see bias and one volt meter to the output to be able to see offset voltage )